Mitt Romney effectively accepted the Republican nomination for president this evening, as he cruised to victory in five primaries and padded his delegate lead over the two other GOP candidates left in the race.

The address appeared to serve as an unveiling for a number of themes likely to re-emerge throughout the campaign against Obama, and Romney attempted to turn the president’s “fairness” message against him, arguing that the commander in chief’s dismal record has led to a condition of “unfairness” for millions of Americans.

Among the more memorable lines from Romney’s speech: “A better America begins tonight” and “It’s still about the economy, and we’re not stupid.”

The Obama campaign responded with a statement charging that Romney wants to return the country “to the same policies that got us into the economic crisis in the first place.”

“Tonight is the start of a new campaign to unite every American who knows in their heart that we can do better,” Romney said. “The last few years have been the best that Barack Obama can do, but it’s not the best America can do. Tonight is the beginning of the end of the disappointments of the Obama years and the start of a new and better chapter that we will write together.

“In the days ahead, I look forward to spending time with many of you personally,” Romney continued. “I want to hear what’s on your mind, hear about your concerns and learn about your families. I want to know what you think we can do to make this country better and what you expect from your next president. And I’ll tell you a little bit about myself. I’ll probably start out talking about my wonderful wife, Ann — I usually do — and I’ll probably bore you with stories about our kids and grandkids.”

Former Speaker Newt Gingrich (Ga.) and Rep. Ron Paul (Texas) have yet to follow ex-Sen. Rick Santorum (Pa.) and drop out of the Republican presidential primary. But since Santorum exited the contest earlier this month, Romney has assumed the mantle of presumptive GOP nominee. The former Massachusetts governor made clear in his address this evening that he is embracing victory, even if some of his opponents refuse to concede defeat.

The Obama campaign, meanwhile, moved to tie Romney to President George W. Bush and charged the candidate with misrepresenting the president’s record.

“The title for Gov. Romney’s speech tonight should have been 'Back to the Future,' because he has proposed a return to the same policies that got us into the economic crisis in the first place,” Obama campaign spokesman Ben LaBolt said. “We have tried those policies before. They didn’t unleash growth, they didn’t spur job creation and they didn’t boost the middle class. And while Mitt Romney praised those policies in 2004, they led to a recovery that produced seven times fewer private sector jobs than the president’s policies, despite a significantly milder recession compared to the one the president faced coming into office.

“This election will be a choice between two candidates, two records and two visions for the country,” LaBolt added.